It does appear that EWR and JFK are approximately equidistant from Penn Station. And I believe that EWR is a direct train ride away from Penn Station via NJT or Amtrak.

By car, I feel it's much faster to EWR than to JFK from mid-town because of the highways. The route to JFK is a lot more "local" i.e. traffic lights.

Using the train is also good but you need to understand how Penn Station works. Due to the limited number of tracks, you won't know which one the train will be on, so you need to wait with everyone on the lobby level above the tracks and watch the time-table board. 5-10mins before the train leaves the track number will get listed and everyone scrambles to the track downstairs. Can be quite confusing for the first-timer!

By car, I feel it's much faster to EWR than to JFK from mid-town because of the highways. The route to JFK is a lot more "local" i.e. traffic lights.

Using the train is also good but you need to understand how Penn Station works. Due to the limited number of tracks, you won't know which one the train will be on, so you need to wait with everyone on the lobby level above the tracks and watch the time-table board. 5-10mins before the train leaves the track number will get listed and everyone scrambles to the track downstairs. Can be quite confusing for the first-timer!

Which of the two airports is more expensive to commute to Manhattan out of (assume that a passenger will not rent a car or be fetched by a friend)?

Which of the two airports is more expensive to commute to Manhattan out of (assume that a passenger will not rent a car or be fetched by a friend)?

I have to confess that I normally take a limo or taxi as I'm usually in NYC mostly on business. The cost is slightly cheaper to EWR than to JFK, assuming similar traffic conditions.

I've only taken the train to EWR (the office is very near Penn Station) and never to JFK (inconvenient from there), so I don't have a cost comparison. But I suspect you will have no problems finding that info by doing a couple of google searches. One thing to note for trains is that it is not so convenient if you have a very large suitcase or lots of luggage as the train is not a dedicated airport train.

Which of the two airports is more expensive to commute to Manhattan out of (assume that a passenger will not rent a car or be fetched by a friend)?

Roughly the same I think.

JFK was Airtrain to Jamaica station followed by the LIRR to Penn station. EWR also provides a direct connection to Penn Station on New Jersey Transit. Both are around $15.

If you want to go to a specific area of Manhattan via the NYC Subway and don't have heavy luggage (be ready for stairs!) then a subway service from Jamaica or Howard's Beach is only about $8 to anywhere in Bronx, Manhattan, Queens or Brooklyn ($5 Airtrain, $3 one-way fare including transfers).

I did JFK to Manhattan using the JFK Airtrain to Jamaica Station, and then the Long Island Rail Road (LIRR) to Penn Station.

Picking the right train at Jamaica Station to Penn Station was a little confusing, but the people around were quite happy to help.

The actual ticket payment system is also a little confusing (you buy tickets from the machines at Jamaica station).

Google Maps was very helpful, although even Google Maps seemed confused about which trains got from Jamaica Station to Penn Station.

All that said, I found getting for JFK to Penn Station via Airtrain/LIRR to be a reasonably quick and efficient journey, and quite inexpensive. I would do it that way again, as the alternatives (taxi etc) are quite expensive.

Interesting TR. Given that no city comes close to NY in terms of being transport-friendly in the US, it is a shame that it does not have an express train that goes nonstop from the city centre to either airport such as is the case in London, Hong Kong, Kuala Lumpur, Stockholm, and Oslo. What I imagine they should do is create an airport express from JFK until Penn then continue to EWR.

Given that no city comes close to NY in terms of being transport-friendly in the US, it is a shame that it does not have an express train that goes nonstop from the city centre to either airport such as is the case in London, Hong Kong, Kuala Lumpur, Stockholm, and Oslo. What I imagine they should do is create an airport express from JFK until Penn then continue to EWR.

Have not yet tried Oslo's airport train, but agree that the others (HKG, LHR, ARN, KUL) are all very convenient. The one that really impressed me was the Arlanda Express from Arlanda to Stockholm. What a nice train, although the cost is as expensive as taking a taxi in some other cities.

In the US, Uber is often the preferred option for me, although I do take the bus/train from BOS, mainly because BOS is so close to the city.

Have not yet tried Oslo's airport train, but agree that the others (HKG, LHR, ARN, KUL) are all very convenient. The one that rally impressed me was the Arlanda Express from Arlanda to Stockholm. What a nice train, although the cost is as expensive as taking a taxi in some other cities.

In the US, Uber is often the preferred option for me, although I do take the bus/train from BOS, mainly because BOS is so close to the city.

If you do get to OSL, the airport train (flytoget) is the only way to get to the city as taxis are horrendously expensive.

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God must have been a ship owner, he placed the raw materials far from where they are needed and covered two-thirds of the earth with water...

^^Flytoget simply means the airport express train in Norwegian. It costs US$23 one-way but discounts exist for certain groups (e.g. students up to 31 get 50% off). Having taken it for three round-trips, it is similar to the Arlanda Express in terms of quality.

There is the alternative NSB (Norwegian state railway) train that goes from city centre to the airport that is half price but about only four to five minutes longer. Think about that as Heathrow Connect but I believe it has WiFi.

^^Flytoget simply means the airport express train in Norwegian. It costs US$23 one-way but discounts exist for certain groups (e.g. students up to 31 get 50% off). Having taken it for three round-trips, it is similar to the Arlanda

Ah...thanks...I should have guessed (Or at least googled.). It sounded a little unusual in English ("Fly to get where?"). My bad.